Dr Marion McAfee
No more applications being accepted
Funded PhD Project (Students Worldwide)
About the Project
Medical implants are increasingly seeing the incorporation of Active Pharmaceutical Ingredients (API) to reduce implant site complications and improve biocompatibility. Such molecules include antibacterial drugs, immunosuppressive drugs, anti-inflammatory drugs, or APIs that in various ways stimulate cellular proliferation and tissue regeneration. Implant materials suited for drug release purposes are typically bioresorbable polymers such as polylactic acid (PLA) which degrade over time into non-toxic byproducts while slowly but continuously releasing the drug trapped within its matrix. Ideally the polymer provides initial mechanical support (e.g. cardiovascular stent, bone fixation screw etc.) and degrades completely over time as the host tissue heal and the implant is no longer required.
The incorporation of drug into polymer can be done in a number of different ways but Hot Melt Extrusion (HME) has a number of advantages over other methods including: enhanced bioavailability of poorly soluble drugs; fewer processing steps; less scale-up issues resulting in a shorter development time; possible automation of the production line; reduction of production costs and waste; a reduced time to market; less product variability and improved product quality.
However HME of such devices is still complex and expensive with long development times - not only in the formulation of the product but also in identifying suitable process conditions and adapting to variations between batches of raw materials. Processing conditions affect the degradation of the polymer, degradation of the drug, drug-polymer interaction, dispersion of the API, the crystallinity of the drug and other factors critical to mechanical properties and drug release behaviour. The effect of process settings on these factors are not well understood and the industry is still dominated by off-line quality testing in a laboratory with very slow feedback to adjusting the process parameters.
The proposed research targets this knowledge gap by aiming to use on-line process measurements, including Process Analytical Technology (PAT) to predict key final product quality characteristics in real-time during processing using mathematical modelling techniques. The successful candidate will research a variety of process sensors; set-up a data acquisition system; run plant trials; carry out a variety of product characterisation tests in the lab and explore modelling techniques capable of predicting the product quality from the available in-process data. Multivariate analysis and machine learning techniques will be explored as appropriate.
The successful candidate will be based at IT Sligo but will also conduct lab research at the Polymer Processing labs at Athlone Institute of Technology (AIT) and at the Pharmaceutical Manufacturing Technology Centre (PMTC) based in the University of Limerick, both centres are collaborators in the research project.
Research questions to be addressed:
1. How do extrusion processing parameters affect the quality of extruded bioresorbable API-loaded medical implants?
2. Can in-process Raman and/or NIR spectroscopy data yield real-time insight to the structure and properties of the drug-polymer systems for the production of such implants?
3. Is it possible to use this data, with or without other process data, to predict final product quality metrics in real-time with similar accuracy to conventional off-line laboratory testing?
The outcomes of the research have the potential to reduce development time and costs of new innovative medical devices with ultimate benefits to patients.
Funding Notes
The bursary will have two elements:
1. A maintenance grant of €13,000 p.a.
2. Tuition fees (currently €819 p.a.) will be paid by the Institute for all holders of student bursaries. Students are required to pay their registration fee. The registration fee for EU students for 2017-2018 is €3,000 p.a
Funding will be initially a maximum of 2 years for a Master’s registration, or, on successful completion of a transfer to PhD, a maximum of 4 years for a PhD.